Oxygen tent



Aug. 21, 1962 A. H. ANDREWS, JR 3,050,058

OXYGEN TENT Filed May 28, 1956 2 Sheets-Sheet 1 Aug. 21, 1962 A. H.ANDREWS, JR 3,050,058

OXYGEN TENT Filed May 28, 1956 2 Sheets-Sheet 2 A/ber/ H Andrews (/1? yjg 3,050,058 X GEN TENT Albert H. Andrews, In, 4714 Greenwood Ave,Chicago 14-, ill. Filed May 28, 1956, Ser. No. 587,860 Claims. (Cl.128191) This invention relates in general to an apparatus foradministering gas therapy, and more particularly to an oxygen tent foradministering oxygen therapy to a bedded patient, wherein the bulk ofthe tent may be placed under the bed thereby conserving needed space insmall rooms. Still more particularly, the oxygen tent of the presentinvention is capable of administering oxygen therapy safely andaccurately, while also attending to the patients comfort.

Heretofore, oxygen tents have included mechanism which was extremelybulky and necessitated occupying considerable needed space in smallrooms. Also, where electrical refrigeration units were employed forcooling and the cooling coils were mounted in the canopy, the patientslife was continually endangered by the possibility that a leak mightdevelop in the cooling coils allowing the refrigerant to escape withinthe canopy. Moreover, difficulty has been encountered in administeringthe proper percentages of oxygen to the canopy for any length of time.Where cooling coils from an electrical refrigeration unit are employedWithin the canopy, a problem is encountered in removing the condensateproduced on the cooling coils by the patient and deflecting the airblown over the cooling coils so that the cool draft does not blowdirectly on the patients head.

The oxygen tent of the present invention comprises a compressor cabinetassembly adapted to be positioned substantially entirely under the bedof a patient, a canopy assembly for positioning above the patients head,and a hollow supporting column and control assembly upstanding from thecabinet assembly along one side of the bed for supporting an overheadcanopy and providing an enclosed housing for connections between thecompressor assembly and the canopy assembly. In the compressor assembly,a refrigeration unit is arranged to have its cooling coils in heatexchange relationship with a set of cooling coils which are connected tocooling coils positioned in the canopy assembly. At the top of thecanopy assembly a blower unit driven by an external motor magneticallyconnected to the blower forces air over the cooling coils therein.Condensate formed on the cooling coils falls into a drip pan. The drippan functions as a baffle to deflect the air driven over the coolingcoils so that it will not blow directly onto the patients head. Oxygenis delivered to the canopy assembly through a pipe having an end open tothe atmosphere outside of the canopy assembly, and terminating insidethe canopy assembly behind the blower unit. A variable valve is providedto selectively control the end of the pipe open to the atmosphere.

While the present invention is primarily concerned with theadministering of oxygen therapy, it will be understood that it may beemployed for administering other types of gas therapy.

Accordingly, it is an object of this invention to provide an improvedapparatus for administering gas therapy which obviates the heretoforeencountered difficulties.

Another object of this invention is in the provision of an apparatus foradministering oxygen therapy, wherein the bulk of the apparatus may bepositioned under the bed thereby conserving needed space in small rooms.

A still further object of this invention resides in the provision of anapparatus for administering oxygen therapy efiiciently and accurately toa bedded patient, while at the same time serving to comfort the patient.

A further object of this invention is to provide an oxy- 3,650,058Patented Aug. 21, 1962 gen tent including a canopy assembly, wherein thetemperature within the canopy is automatically controlled in accordancewith the comfort desires of the patient.

A still further object of this invention is in the provision of anoxygen tent having an electrical refrigeration unit for regulating thetemperature within the canopy, wherein the cooling coils of therefrigeration unit are mounted outside the canopy and means is providedin communication with the cooling coils of the refrigeration unit andthe inside of the canopy to remove heat from within the canopy.

Another object of this invention resides in the provision of an oxygentent including a canopy assembly having heat exchange coils within thecanopy and a blower unit for circulating the air within the canopy overthe heat exchange coils, and means is provided to catch the condensatedrippings from the coils and deflect the cool draft so that it does notblow directly on the patients head.

Another object of this invention is to provide an oxygen tent haivng anarrangement for delivering accurately various amounts of oxygen to thecanopy according to the desires and needs of the patient.

Still another object of this invention is in the provision of a blowerunit mounted on a panel or wall, wherein the motor is positioned on oneside of the panel and the fan is positioned on the other side, andwherein leakage of atmosphere between the sides of the panel iseliminated.

A still further object of this invention is to provide an oxygen tenthaving an electric motor operated blower unit mounted thereon, whereinthe fan is positioned within the canopy assembly and the electric motoris mounted on the outside of the assembly, and means is provided toabsolutely prevent leakage of oxygen from within the canopy asserrrblyat the motor mount.

A still further object of this invention resides in the provision of amagnetic coupling drive for transmitting rotary motion through a wall orpanel which includes a driving member on one side of the wall and adriven member on the other side of the wall and means for preventing anyleakage of air through the wall.

A further object of this invention is to provide an oxygen tent havingan oxygen flow assembly and a canopy assembly, wherein an oxygen leak inthe flow assembly will not raise the oxygen concentration in the canopyand wherein cut off of the oxygen will not hinder admittance of air.

Other objects, features, and advantages of the invention will beapparent from the following detailed disclosure, taken in conjunctionwith the accompanying sheets of drawings, wherein like referencenumerals refer to like parts, in which:

As shown on the drawings:

FIGURE 1 is a generally diagrammatic view, with some parts shown insection and others in elevation of an oxygen tent according to theinvention;

FIGURE 2 is an enlarged detail sectional view of the valve whichcontrols drainage of the water carrying heat exchange coils and fillingof the coils by clean water;

FIGURE 3 is a greatly enlarged fragmentary view of a portion of thecanopy assembly showing the magnetic coupling drive and sealingarrangement of the electrical motor driven blower;

FIGURE 4 is a fragmentary and greatly enlarged diagrammatic sectionalview illustrating the oxygen flow assembly for controlling thepercentage of oxygen to be delivered to the canopy assembly; and

FIGURE 5 is a plan view of the control disk-employed in the oxygen flowcontrol valve of FIGURE 4.

On the drawings:

Referring particularly to FIGURE 1, the oxygen tent of the instantinvention includes a compressor or cabinet assembly 10, a canopyassembly 11, a tubular'support or column 12 for supporting the canopyassembly 11 and providing a housing for connecting elements between thecanopy assembly and the cabinet assembly, and an oxygen flow assembly13. These main components are in their approximate assembledrelationship, wherein the tubular support and housing 12 is anchored atits bottom end to the frame of the compressor assembly 18. The tubularsupport and housing is therefor upstanding from the compressor assemblyand provided with a eurvate section at its upper end which overlies themain portion of the compressor assembly 10 since the bottom end issuitably anchored at one side thereof.

The compressor assembly includes a housing 14 which is rectangular inshape, in this instance, and which serves as a base for the oxygen tentthat may rest on the floor. To facilitate moving the oxygen tent alongthe floor, the housing 14 of the compressor assembly may be providedwith a plurality of casters on the bottom thereof, these not being shownfor purposes of clarity. At the upper end of the tubular support andhousing 12 the curvate portion which extends over the housing 14 of thecompressor assembly 10 has rigidly secured thereto a dome-shaped memberor hood 15 of the canopy assembly. Thus, it will be noted that thedome-shaped member 15 of the canopy assembly 11 is positioned above themain portion of the compressor assembly housing 14. At the outerperiphery of the canopy hood 15, suitable clamping or securing means,such as indicated by the numeral 16 is provided to detachably connect a.flexible canopy 17 thereto defining with said hood an oxygenconditioning chamber 17a. This canopy can be made of any suitablematerial, but preferably of pliofilm which is relatively inexpensive andmay be discarded after use, and which is transparent thereby allowingthe patient to see out.

In the compressor assembly housing 14, an electric refrigeration unit 18having a set of cooling coils 19 serves to provide the necessary coolingfor the atmosphere in the canopy 17. The cooling coils 19 are in heatexchange relationship with a set of heat exchange coils 20 which areoperatively connected to a similar set of heat exchange coils or coolingcoils 21 mounted in the canopy assembly 11, the connecting tubularportions extending through the tubular support housing 12. These heatexchange coils are adapted to carry a coolant fluid, such as water whicheffects removal of heat within the canopy assembly. A waterrecirculating pump 22 is provided in one of the connecting lines betweenthe heat exchange coils 20 and 21 for circulating the water therein.This pump is also mounted in the compressor assembly housing 14. Sincethe cooling coils 19 of the refrigeration unit 18 are mounted outside ofthe canopy 17, any possibility of a refrigerant leaking from these coilsand mixing with the atmosphere within the canopy 17 has been obviated.Obviously, leakage of water from the cooling coils 21 within the canopyassembly 11 would not in any way be detrimental to a patient undergoingoxygen therapy in the oxygen tent, while leakage of the refrigerant gasin the tent would obviously interfere with the oxygen concentrationwhich would be undesirable. In fact, where poisonous refrigerants areemployed, death of the patient could easily come about. But the leakageof water within the canopy would not affect the concentration of oxygen.

Should it be desired to change the water in the water carrying coils 20and 21, a four-way valve 23 is provided having four ports 24, 25, 26 and27, wherein the adjacent ports may be in communication at any one timeupon manipulation of a center plug 28 having angular passageways 28a and28b therethrough. Ports 24 and 25 are connected in a line of the watercarrying coils 20 and 21 at 24a and 25a, respectively, and the valveplug 28 will normally be positioned as shown in FIGURE 2 so that ports24 and 25 are intercommunicated by the passageway 28a and recirculationof the water through the heat exchange coils 2i} and 21 by the pump 22is maintained. Port 26 is connected to a line 29 leading to a drain line'30. Rotation of the valve plug 28 so that ports 25 and 26, and 24 and27 are intercommunicated allows the Water-carrying coils 2G and 21 to bedrained of the water or cooling fluid. In this position of the plug 28,water is allowed to drain down, both sides of the water-carrying coilsthrough lines 29 and 30 from the port 26, and through a combinationwater supply and drain line 31, and drain line 31a from the port 27. Ashut-off drain valve 31b is positioned in the drain line 31a, and openedduring the draining operation.

The combination line 31 is also connected through a shut-off water valve310 to a water supply or reservoir 32. During the draining operation thevalve 310 will be closed. While the valve plug 28 is stationed in thedraining position, filling of the water-carrying coils with fresh watermay be accomplished. The drain valve 31b is closed and the water valve31c is opened. When the coils are full, water will be discharging fromthe drain line 30, at which time rotation of the valve plug 28 to itsoriginal position so that ports 24 and 25 are connected will place thesystern back in operation. Water valve 31c may then be closed.

In order to control the temperature of the atmosphere within the canopy,an adjustable temperature control assembly or thermostat 33 is providedwhich includes a temperature sensitive element 34 positioned within thecanopy assembly to be subjected to the conditions of the atmospheretherein and which is suitably connected to the control 33a by a line 35,and suitable connectors 36 leading to the refrigerating unit 18 throughthe tubular support 12. Manual adjustment of the thermostat 33a effectscontrol of the temperature within the canopy by controlling theoperation of the refrigerating unit 18.

Included in the canopy assembly 11 is a blower unit 37 (shown mostclearly in FIGURE 3) which circulates the atmosphere within the canopy17 over the cooling coils or heat exchange coils 21. In order to mountthe blower unit 37 on the hood or dome-shaped member 15 of the canopyassembly 11, an opening is formed in the center of the hood forreceiving a mounting and supporting plate 38 having an outstandingflange 38a in overlying relationship with the hood 15. A plurality offasteners 39 extend through the flange 38a and are threadedly receivedin the hood 15 for securing the plate 38 to the hood. Between the flange38a and the hood 15, a gasket 46 is positioned for preventing thepossibility of any leakage of oxygen from within the canopy assembly.The mounting plate 38 is provided with a center bore 41 which receives apair of bearings 42 for rotatably supporting a fan shaft or driven shaft43. On the end of the shaft 43 extending within the hood, a fan blade 44is removably carried and positioned overhead of the heat exchange coils21. An electric motor 45 of any suitable type is supported on the sideof the mounting plate 38 which is outside of the hood by a flangedmounting ring 46. Suitable fasteners 47 secure the flange of themounting ring 46 to the mounting plate 38.

The electric motor 45 is provided with a drive shaft 48, and a magneticcoupling is employed to drivingly connect this shaft with the fan shaft43. This magnetic coupling includes a permanent magnet 49 in the shapeof a disk which is secured to the very end of the shaft 48 and protrudeswithin a recessed portion of the mounting plate 38 defined by anenlarged counterbore St in communication with the bore 41. Also includedin the magnetic coupling is a magnetically susceptible cup-shaped member51 secured on the inner end of the driven shaft 43 and sized topartially freely telescope over the permanent magnet 49. Preferably, thecup-shaped magnetically susceptible member 51 may be constructed of softiron. Extending between the permanent magnet 49 and the soft iron drivenmember of the magnetic coupling is a nonmagnetic contoured sheet ofmaterial 52 having its outer periphery securely clamped between theflange of the mounting ring 46 and the upper face of the mounting plate38 in order to define a seal which -will act to prevent leakage ofoxygen from within the canopy assembly. A flexible O-ring 53 guardsagainst leakage between the sealing member 52 and the mounting plate 38.As already pointed out, the sealing member necessarily is constructed ofnon-magnetic material and is preferably constructed of a relativelyrigid material, such as aluminum. Thus, operation of the electric motor45 drives the fan blade 44 through the shafts and the magnetic couplingwithout any danger of oxygen escaping from within the canopy assembly.This sealing arrangement increases the safeness of use of the oxygentent, wherein leakage of oxygen to the electric motor which might causea fire has been eliminated. Further, leakage around the blower wouldupset the oxygen concentration.

The cooling unit within the canopy assembly 11 removes the heat andwater vapor produced by the patient and thus maintains a comfortableatmosphere. Condensate formed on the cooling coils 21 drops into a collecting pan 54 which underlies the cooling coils and is provided with adrain line 55 running over to the tubular housing support 12 anddownwardly through the housing support to the drain line 30. Thus, thecondensate is removed by gravity through the drain line 55 and the drainline 30. Additionally, the collecting pan 54 serves as a bafile ordeflector which prevents the cool draft created by the blower unit 37from blowing directly on the patients head.

The oxygen fiow assembly 13 controls the oxygen concentration within thecanopy, and includes a pipe 56 terminating within the canopy at a pointbehind the fan blade 44 and at the outside of the canopy in an .open endat 57. Oxygen is supplied from a source 58, such as an oxygen tank, anddelivered through a suitable conduit 59 to a reducing valve 60 whichgreatly reduces the pressure and controls the oxygen flow, and through ashutoff valve 61. The conduit 59 terminates within the oxygen feed pipe56 and is provided ,on the side facing the outlet end of a pipe with anaperture or opening 62. Spaced inwardly from the open end 57 of the pipe56 is a slot which receives an outer portion of a rotatable disk 63. Thedisk 63 is carried on a shaft 64 rotatably mounted in a bearing 65 andcapable of being rotatably manipulated by a knurled knob 66. A pluralityof circumferentially spaced apertures 67, 68, 69, 70, 71 and 72 areformed in the rotatable disk 63 for varying the openings at the outerend of the pipe 56 in order to vary the oxygen concentration deliveredto the inside of the canopy. With the largest opening 72 in line withthe pipe 56, the greatest amount of outside air is drawn through theopen end of the pipe 57 by the jet effect of oxygen exiting from theaperture to dilute the oxygen delivered from the aperture 62, while thesmallest opening 67 permits much less air to enter the open end of thepipe 56' thereby delivering a larger concentration of oxygen to theinside of the canopy. Further, rotation of the fan 44 creates a suctionon the side next to the hood 15 which operates on the open end of thepipe 56 to aid in drawing the oxygen and air into the canopy. If it isdesired to deliver 100% oxygen to the inside of the canopy, the disk 63may be rotated so that the solid portion between apertures 67 and 72completely closes off the end of the pipe 56 and prevents any air fromentering the pipe.

In operation, the oxygen tent of the present invention is employed foradministering oxygen therapy to bedded patients. In positioning theoxygen tent with respect to the bedded patient, the compressor assemblyhousing 14 is slid under the bed in such a manner that the canopyassembly 11 will be positioned substantially directly overhead of thepatients head. This positions the tubular supporting column 12 at oneside of the bed, thereby necessitating only a small portion of thecompressor assembly housing to project from under the bed' Thus, only asmall amount of extra floor space is taken, thereby conserving muchneeded space in small rooms. The lower edges of the canopy 17 will thenbe suitably tucked under the covers or mattress of the bed in order tocompletely enclose the patients head and shoulders within the canopy.Starting of the refrigeration unit 18, the blower unit 37 and the watercirculating pump 22 establishes the cooling unit of the tent inoperation. Control of the temperature of the atmosphere within thecanopy 17 is then obtained through the temperature control assembly 33,which operates to energize and deenergize the refrigeration unit 18 inaccordance with the temperature within the canopy. The oxygenconcentration valve is then adjusted to bring the desired concentrationaperture on the disk 66 in alignment with the open end of the oxygenfeed pipe 56, and the oxygen is admitted to the feed pipe 56 bymanipulation of the shut-off valve and the reducing valve 60. Byselectively manipulating the disk 63 of the oxygen concentration valve,the concentration of oxygen within the canopy can be adjusted.

From the foregoing, it is seen that the instant invention provides animproved oxygen tent that is easy to operate, safer in construction forthe benefit of the patient, -arranged to conserve badly needed space insmall roms, capable of accurately controlling the temperature and oxygenconcentration within the canopy in accordance with the patients comfortand is eflicient in operation.

It will be understood that modifications and variations may be eifectedwithout departing from the scope of the novel concepts of the presentinvention, but it is understood that this application is to be limitedonly by the scope of the appended claims.

I claim as my invention:

1. Apparatus for administering oxygen therapy comprising a cabinetassembly, a tubular member extending upwardly from said cabinetassembly, a hood carried by said tubular member in overlyingrelationship to said cabinet assembly, a canopy suspended from said hoodfor draping over the head of a patient, means for cooling the atmospherewithin said canopy including a refrigeration unit in said cabinetassembly having a set of cooling coils, a first set of coolant-carryingcoils in heat exchange relationship with said cooling coils, a secondset of coolantcarrying coils mounted under said hood and being connectedto said first set of coolant-carrying coils, means for circulatingcoolant through said coolant-carrying coils, and means for introducingoxygen into said canopy.

2. Apparatus for administering oxygen therapy comprising a cabinetassembly, a tubular member extending upwardly from said cabinetassembly, a hood carried by said tubular member in overlyingrelationship to said cabinet assembly, a canopy suspended from said hoodfor draping over the head of a patient, means for cooling the atmospherewithin said canopy including a refrigeration unit in said cabinetassembly having a set of cooling coils, a first set of coolant-carryingcoils in heat exchange relationship with said cooling coils, a secondset of coolantcarrying coils mounted under said hood and being connectedto said first set of coolant-carrying coils, means for circulatingcoolant through said coolant-carrying coils, means mounted on said hoodfor circulating the atmosphere within the canopy over said second set ofcoolant carrying coils, and means for introducing oxygen into saidcanopy.

3. Apparatus for administering oxygen therapy comprising a cabinetassembly, a tubular member extending upwardly from said cabinetassembly, a hood carried by said tubular member in overlyingrelationship to said cabinet assembly, a canopy suspended from said hoodfor draping over the head of a patient, means for cooling the atmospherewithin said canopy including a refrigeration unit in said cabinetassembly having a set of cooling coils, a first set of coolant-carryingcoils in heat exchange relationship with said cooling coils, a secondset of coolantcarrying coils mounted under said hood and being connectedto said first set of coolant-carrying coils, means for.

circulating coolant through said coolant-carrying coils, means mountedon said hood for circulating the atmosphere within the canopy over saidsecond set of coolant carrying coils, means underlying said coolantcoils mounted under said hood for collecting condensate and deflectingthe atmosphere circulating thereover, and means for introducing oxygeninto said canopy.

4. Apparatus for administering oxygen therapy comprising a cabinetassembly, a tubular member extending upwardly from said cabinetassembly, a hood carried by said tubular member in overlyingrelationship to said cabinet assembly, a canopy suspended from said hoodfor draping over the head of a patient, means for cooling the atmosphereWithin said canopy including a refrigeration unit in said cabinetassembly having a set of cooling coils, a first set of coolant-carryingcoils in heat exchange relationship with said cooling coils, a secondset of coolantcarrying coils mounted under said hood and being connectedto said first set of coolant-carrying coils, means for circulatingcoolant through said coolant-carrying coils, means mounted on said hoodfor circulating the atmosphere within the canopy over said second set ofcoolant carrying coils, a collecting pan underlying said second set ofcoolant-carrying coils for collecting condensate drippings from saidcoils and for deflecting the atmosphere circulating thereover, and meansfor introducing oxygen into said canopy.

5. Apparatus for administering oxygen therapy comprising a cabinetassembly, a tubular member extending upwardly from said cabinetassembly, a hood carried by said tubular member in overlyingrelationship to said cabinet assembly, a canopy suspended from said hoodfor draping over the head of a patient, means for cooling the atmospherewithin said canopy including a refrigeration unit in said cabinetassembly having a set of cooling coils, a first set of coolant-carryingcoils in heat exchange relationship with said cooling coils, a secondset of coolant-carrying coils mounted under said hood and beingconnected to said first set of coolantcar-rying coils, means forcirculating coolant through said coolant-carrying coils, means countedon said hood for circulating the atmosphere within the canopy over saidsecond set of coolant-carrying coils, a combination drip pan anddeflector for collecting condensate dripping from the coils anddiver-ting the flow of circulating atmosphere so that it will not blowdirectly on the patients head, and means for introducing oxygen intosaid canopy.

6. Apparatus for administering oxygen therapy to a patient in a bedwhich comprises a cabinet adapted to be supported on the floor to bepositioned substantially under the bed, an electrical refrigeration unitcarried in said cabinet and having a set of cooling coils, a tubularmember extending upwardly from said cabinet at one end thereof to bepositioned at one side of the bed, a domeshaped hood carried at theupper end of said tubular member in overlying relation to said cabinetand therefore to be positioned directly over the bed, a canopy suspendedfrom the periphery of said hood, a first set of water carrying coils insaid cabinet in heat exchange relationship with said refrigeratorcooling coils, a second set of water carrying coils mounted under saidhood, conduits extending through said tubular member connecting saidsets of water-carrying coils, a circulating pump in said cabinet forcirculating water through said water-carrying coils, a blower unitmounted on said hood for circulating the atmosphere within the canopyover the second set of water-carrying coils, a pan underlying saidsecond set of water-carrying coils for collecting condensate anddeflecting the atmosphere so that it does not directly strike thepatients head, a drain leading from the pan and downwardly through saidtubular member, and an oxygen flow assembly for introducing a selectedoxygen concentration into said canopy.

7. Apparatus for administering oxygen therapy to a patient in a bedwhich comprises a cabinet adapted to be supported on the floor and to bepositioned substan tially under the bed, an electrical refrigerationunit carried in said cabinet and having a set of cooling coils, atubular member extending upwardly from said cabinet at one end thereofto be positioned at one side of the bed, a dome-shaped hood carried atthe upper end of said tubular member in overlying relation to saidcabinet and therefore to be positioned directly over the bed, a canopysuspended from the periphery of said hood, :1 first set ofwater-carrying coils in said cabinet in heat exchange relationship withsaid refrigerator cooling coils, a second set of water-carrying coilsmounted under said hood, conduits extending through said tubular memberconnecting said sets of Water-carrying coils, a circulating pump in saidcabinet for circulating water through said Water-carrying coils, ablower unit mounted on said hood for circulating the atmosphere Withinthe canopy over the second set of water-carrying coils, a pan underlyingsaid second set of water-carrying coils for collecting condensate anddeflecting the atmosphere so that it does not directly strike thepatients head, a drain leading from the pan and downwardly through saidtubular memher, a variable control having a temperature sensitiveelement responding to the temperature of the atmosphere in said canopyand being operatively connected to said refrigeration unit forcontrolling same, and an oxygen flow assembly for introducing a selectedoxygen concentration into said canopy.

8. Apparatus for administering oxygen therapy to a patient in a bedwhich comprises a cabinet adapted to be supported on the floor and to bepositioned substantially under the bed, an electrical refrigeration unitcarried in said cabinet and having a set of cooling coils, a tubularmember extending upwardly from said cabinet at one end thereof to bepositioned at one side of the bed, a dorne-shaped hood carried at theupper end of said tubular member in overlying relation to said cabinetand therefore to be positioned directly over the bed, a canopy suspendedfrom the periphery of said hood, a first set of water-carrying coils insaid cabinet in heat exchange relationship with said refrigeratorcooling coils, a second set of water-carrying coils mounted under saidhood, conduit-s extending through said tubular member connecting saidsets of water-carrying coils, a circulating pump in said cabinet forcirculating water through said watercarrying coils, a (blower unitmounted on said hood for for circulating the atmosphere within thecanopy over the second set of water-carrying coils, a pan underlyingsaid second set of water-carrying coils for collecting condensate anddeflecting the atmosphere so that it does not directly strike thepatients head, a drain leading from the pan and downwardly through saidtubular member, a variable control having a temperature sensitiveelement responding to the temperature of the atmosphere in said canopyand being operatively connecting to said refrigeration unit forcontrolling same, and an oxygen flow assembly for introducing a selectedoxygen concentration into said canopy, said oxygen flow assemblyincluding a tube having one end opening inside of the canopy so theblower unit creates a suction flow therethrough and the other endopening to the outside atmosphere, means for variably restricting theopening to the atmosphere, and means for introducing oxygen into thetube intermediate the ends thereof.

9. Apparatus for administering oxygen therapy to a patient in a bedwhich comprises a cabinet adapted to be supported on the floor and to bepositioned substantially under the bed, an electrical refrigeration unitcarried in said cabinet and having a set of cooling coils, a tubularmember extending upwardly from said cabinet at one end thereof to bepositioned at one side of the bed, a dome-shaped hood carried at theupper end of said tubular member in overlying relation to said cabinetand therefore to be positioned directly over the bed, a canopy suspendedfrom the periphery of said hood, a first set of Water-carrying coils insaid cabinet in heat exchange relationship with said refrigeratorcooling coils, a second set of water-carrying coils mounted under saidhood, conduits extending through said tubular member connecting saidsets of Water-carrying coils, a circulating pump in said cabinet forcirculating water through said water-carrying coils, a blower unitmounted on said hood for circulating the atmosphere within the canopyover the second set of Water-carrying coi'ls, a pan underlying saidsecond set of water-carrying coils for collecting condensate anddeflecting the atmosphere so that it does not directly strike thepatients head, a drain leading from the pan and downwardly through saidtubular member, a variable control having a temperature sensitiveelement responding to the temperature of the atmosphere in said canopyand being operatively connected to said re frigeration unit forcontrolling same, and an oxygen flow assembly for introducing a selectedoxygen concentration into said canopy, said oxygen flow assemblyincluding a tube having one end opening inside of the canopy so theblower unit creates a suction flow therethrough and the other endopening to the outside atmosphere, means for variably restricting theopening to the atmosphere, and an oxygen supply conduit connected to thetube downstream from the end of the tube opening to the atmosphere forintroducing oxygen into the tube.

10, An apparatus for administering oxygen therapy to a patient in a bedwhich comprises a canopy assembly including a hood for directing anoxygen atmosphere downwardly to a patient in a bed, means for inducing aselected oxygen concentration into the canopy, means defining an openingin said hood, a panel secured to the hood and located in said openingwith an opening through said panel, a mounting plate in said openingsealingly secured to said panel, and an axial opening therethrough, afan shaft rotatably mounted in said axial opening and extending from oneside of said plate, a fan carried on the free end of said shaftoperative to circulate the oxygen atmosphere within the canopy, a motorsecured to the other side of said plate and having a drive shaft insubstantial axial alignment with said fan shaft, means for magneticallycoupling said shafts including a permanent magnet carried on one shaftin operative driving relation to a magnetically susceptible membercarried on the other shaft, and a non-magnetic shield extending betweensaid magnet and said magnetically susceptible member and beingperipherally sealed so that the motor is completely sealed from the fanand the oxygen atmosphere cannot contact the motor creating thepossibility of a configuration and whereby the oxygen concentrationcannot be upset by ambient air entering the canopy.

References Cited in the file of this patent UNITED STATES PATENTS2,104,589 Hartman Jan. 4, 1938 2,115,482 Crewe Apr. 26, 1938 2,366,562Schug Jan. 2, 1945 2,479,906 Cole Aug. 23, 1949 2,498,342 Pettiorew Feb.21, 1950 2,510,356 Werts June 6, 1950 2,702,546 Gilroy et al. Feb. 22,1955 2,738,127 Howard Mar. 13, 1956 2,742,040 Moore et al. Apr. 17, 1956FOREIGN PATENTS 393,650 Germany Sept. 2, 1924

